How to export 3d object as a .tri file? blender 2.77
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Export of creations made with Blender to Raydium is possible using the Python script triEXP * comes with sources Raydium.
Use:
Load this script into Blender (BlenderChargerScript), &quot;triangulate&quot; the object in Blender (CTRL + T, in edit mode, after you select all the point with the key), and run the script (ALT + P in the window contains the Python script). This operation performed, a file dialog appears where you can choose the export and the name of the file directory.
You will have a little more information in the console from which you started Blender, especially in case of errors.
!! Warning !! verify that you are in object mode before running the script.
Note: This script does not export the path to the textures, and therefore considers that the textures are always in the same directory as the exported .tri.
See also, for other import / export solutions ImportExportTri

If you look in the source download you will find a blender folder that has several scripts, the startup/tri_import_export_264.py can be loaded in blender's text editor and run to add the .tri import/export options. A simple test shows it to work, if it fails with your models than ask for help improving it with info and examples of what fails.